1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
|
<!--[metadata]>
+++
title = "pull"
description = "The pull command description and usage"
keywords = ["pull, image, hub, docker"]
[menu.main]
parent = "smn_cli"
+++
<![end-metadata]-->
# pull
Usage: docker pull [OPTIONS] NAME[:TAG] | [REGISTRY_HOST[:REGISTRY_PORT]/]NAME[:TAG]
Pull an image or a repository from the registry
-a, --all-tags Download all tagged images in the repository
--disable-content-trust=true Skip image verification
--help Print usage
Most of your images will be created on top of a base image from the
[Docker Hub](https://hub.docker.com) registry.
[Docker Hub](https://hub.docker.com) contains many pre-built images that you
can `pull` and try without needing to define and configure your own.
To download a particular image, or set of images (i.e., a repository),
use `docker pull`.
## Proxy configuration
If you are behind an HTTP proxy server, for example in corporate settings,
before open a connect to registry, you may need to configure the Docker
daemon's proxy settings, using the `HTTP_PROXY`, `HTTPS_PROXY`, and `NO_PROXY`
environment variables. To set these environment variables on a host using
`systemd`, refer to the [control and configure Docker with systemd](../../admin/systemd.md#http-proxy)
for variables configuration.
## Examples
### Pull an image from Docker Hub
To download a particular image, or set of images (i.e., a repository), use
`docker pull`. If no tag is provided, Docker Engine uses the `:latest` tag as a
default. This command pulls the `debian:latest` image:
```bash
$ docker pull debian
Using default tag: latest
latest: Pulling from library/debian
fdd5d7827f33: Pull complete
a3ed95caeb02: Pull complete
Digest: sha256:e7d38b3517548a1c71e41bffe9c8ae6d6d29546ce46bf62159837aad072c90aa
Status: Downloaded newer image for debian:latest
```
Docker images can consist of multiple layers. In the example above, the image
consists of two layers; `fdd5d7827f33` and `a3ed95caeb02`.
Layers can be reused by images. For example, the `debian:jessie` image shares
both layers with `debian:latest`. Pulling the `debian:jessie` image therefore
only pulls its metadata, but not its layers, because all layers are already
present locally:
```bash
$ docker pull debian:jessie
jessie: Pulling from library/debian
fdd5d7827f33: Already exists
a3ed95caeb02: Already exists
Digest: sha256:a9c958be96d7d40df920e7041608f2f017af81800ca5ad23e327bc402626b58e
Status: Downloaded newer image for debian:jessie
```
To see which images are present locally, use the [`docker images`](images.md)
command:
```bash
$ docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
debian jessie f50f9524513f 5 days ago 125.1 MB
debian latest f50f9524513f 5 days ago 125.1 MB
```
Docker uses a content-addressable image store, and the image ID is a SHA256
digest covering the image's configuration and layers. In the example above,
`debian:jessie` and `debian:latest` have the same image ID because they are
actually the *same* image tagged with different names. Because they are the
same image, their layers are stored only once and do not consume extra disk
space.
For more information about images, layers, and the content-addressable store,
refer to [understand images, containers, and storage drivers](../../userguide/storagedriver/imagesandcontainers.md).
## Pull an image by digest (immutable identifier)
So far, you've pulled images by their name (and "tag"). Using names and tags is
a convenient way to work with images. When using tags, you can `docker pull` an
image again to make sure you have the most up-to-date version of that image.
For example, `docker pull ubuntu:14.04` pulls the latest version of the Ubuntu
14.04 image.
In some cases you don't want images to be updated to newer versions, but prefer
to use a fixed version of an image. Docker enables you to pull an image by its
*digest*. When pulling an image by digest, you specify *exactly* which version
of an image to pull. Doing so, allows you to "pin" an image to that version,
and guarantee that the image you're using is always the same.
To know the digest of an image, pull the image first. Let's pull the latest
`ubuntu:14.04` image from Docker Hub:
```bash
$ docker pull ubuntu:14.04
14.04: Pulling from library/ubuntu
5a132a7e7af1: Pull complete
fd2731e4c50c: Pull complete
28a2f68d1120: Pull complete
a3ed95caeb02: Pull complete
Digest: sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2
Status: Downloaded newer image for ubuntu:14.04
```
Docker prints the digest of the image after the pull has finished. In the example
above, the digest of the image is:
sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2
Docker also prints the digest of an image when *pushing* to a registry. This
may be useful if you want to pin to a version of the image you just pushed.
A digest takes the place of the tag when pulling an image, for example, to
pull the above image by digest, run the following command:
```bash
$ docker pull ubuntu@sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2
sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2: Pulling from library/ubuntu
5a132a7e7af1: Already exists
fd2731e4c50c: Already exists
28a2f68d1120: Already exists
a3ed95caeb02: Already exists
Digest: sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2
Status: Downloaded newer image for ubuntu@sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2
```
Digest can also be used in the `FROM` of a Dockerfile, for example:
```Dockerfile
FROM ubuntu@sha256:45b23dee08af5e43a7fea6c4cf9c25ccf269ee113168c19722f87876677c5cb2
MAINTAINER some maintainer <maintainer@example.com>
```
> **Note**: Using this feature "pins" an image to a specific version in time.
> Docker will therefore not pull updated versions of an image, which may include
> security updates. If you want to pull an updated image, you need to change the
> digest accordingly.
## Pulling from a different registry
By default, `docker pull` pulls images from Docker Hub. It is also possible to
manually specify the path of a registry to pull from. For example, if you have
set up a local registry, you can specify its path to pull from it. A registry
path is similar to a URL, but does not contain a protocol specifier (`https://`).
The following command pulls the `testing/test-image` image from a local registry
listening on port 5000 (`myregistry.local:5000`):
```bash
$ docker pull myregistry.local:5000/testing/test-image
```
Registry credentials are managed by [docker login](login.md).
Docker uses the `https://` protocol to communicate with a registry, unless the
registry is allowed to be accessed over an insecure connection. Refer to the
[insecure registries](daemon.md#insecure-registries) section for more information.
## Pull a repository with multiple images
By default, `docker pull` pulls a *single* image from the registry. A repository
can contain multiple images. To pull all images from a repository, provide the
`-a` (or `--all-tags`) option when using `docker pull`.
This command pulls all images from the `fedora` repository:
```bash
$ docker pull --all-tags fedora
Pulling repository fedora
ad57ef8d78d7: Download complete
105182bb5e8b: Download complete
511136ea3c5a: Download complete
73bd853d2ea5: Download complete
....
Status: Downloaded newer image for fedora
```
After the pull has completed use the `docker images` command to see the
images that were pulled. The example below shows all the `fedora` images
that are present locally:
```bash
$ docker images fedora
REPOSITORY TAG IMAGE ID CREATED SIZE
fedora rawhide ad57ef8d78d7 5 days ago 359.3 MB
fedora 20 105182bb5e8b 5 days ago 372.7 MB
fedora heisenbug 105182bb5e8b 5 days ago 372.7 MB
fedora latest 105182bb5e8b 5 days ago 372.7 MB
```
## Canceling a pull
Killing the `docker pull` process, for example by pressing `CTRL-c` while it is
running in a terminal, will terminate the pull operation.
```bash
$ docker pull fedora
Using default tag: latest
latest: Pulling from library/fedora
a3ed95caeb02: Pulling fs layer
236608c7b546: Pulling fs layer
^C
```
> **Note**: Technically, the Engine terminates a pull operation when the
> connection between the Docker Engine daemon and the Docker Engine client
> initiating the pull is lost. If the connection with the Engine daemon is
> lost for other reasons than a manual interaction, the pull is also aborted.
|
